Pinpoint Test H: DTC B1676
Climate Control System
Pinpoint Test H: DTC B1676
Refer to Wiring Diagram Set 55, Automatic Climate Control System for schematic and connector information. Diagrams By Number
Normal Operation
Under normal operation, the HVAC module is grounded through circuit 57 (BK). The HVAC module receives battery voltage through circuit 1566 (RD/YE) and ignition voltage through circuit 1812 (BN/WH).
- DTC B1676 (Battery Voltage Out of Range) - The module senses when voltage is less than 9 volts or greater than 16 volts.
This pinpoint test is intended to diagnose the following:
- Fuse(s)
- Wiring, terminals or connectors
PINPOINT TEST H: DTC B1676
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H1 RETRIEVE ALL CMDTCs IN ALL MODULES
- Enter the following diagnostic mode on the scan tool: Self Test - All CMDTCs.
- Is B1317, B1318 or B1676 present in more than one module AND P0563, P0620, P0625, P0626 or P065B present in the PCM?
Yes
REFER to Charging System Testing and Inspection for diagnosis of the battery and charging system. CLEAR all CMDTCs. TEST the system for normal operation.
No
GO to H2.
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H2 CHECK BATTERY CONDITION
- Refer to Battery, Mounting and Cables Testing and Inspection and carry out the Battery - Condition Test. Pinpoint Tests
- Does the battery pass the condition test?
Yes
If the battery passed the condition test but required a recharge, REFER to Charging System Testing and Inspection to diagnose the charging system. CLEAR all CMDTCs. TEST the system for normal operation. If the battery passed the condition test and did not require a recharge, GO to H3.
No
INSTALL a new battery. CLEAR all CMDTCs. TEST the system for normal operation.
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H3 CHECK CHARGING SYSTEM VOLTAGE
NOTE: Do not allow the engine speed to increase above 2,000 rpm while performing this step or the generator may self excite and result in default charging system output voltage. If engine speed goes above 2,000 rpm, shut the vehicle OFF and restart the engine before performing this step.
- Measure the voltage of the battery with and without a load on the charging system as follows:
- Turn off all accessories and run the engine at 1,500 rpm for a minimum of 2 minutes while measuring battery voltage.
- Turn on headlights and HVAC fan on high and run engine at 1,500 rpm for a minimum of 2 minutes while measuring battery voltage.
- Are the voltages between 13 and 15.2 volts?
Yes
GO to H4.
No
REFER to Charging System Testing and Inspection to diagnose the charging system. CLEAR all CMDTCs. TEST the system for normal operation.
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H4 CHECK FOR VOLTAGE MONITORING THE MODULE SUPPLY VOLTAGE (VBAT_CC) HVAC PID
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: VBAT_CC HVAC PID.
- Monitor the battery voltage VBAT_CC HVAC PID.
- Is the battery voltage less than 9 or greater than 15.5 volts?
Yes
If voltage is less than 9 volts, GO to H5.
If voltage is greater than 15.5 volts, INSTALL a new HVAC module. REFER to Climate Control Service and Repair. CLEAR all CMDTCs. REPEAT the self-test.
No
GO to H8.
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H5 CHECK CIRCUIT 57 (BK) FOR AN OPEN
- Ignition OFF.
- Disconnect: HVAC Module C228A.
- Measure the resistance between HVAC module C228A-2, circuit 57 (BK), harness side and ground.
- Is the resistance less than 5 ohms?
Yes
GO to H6.
No
REPAIR circuit 57 (BK) for an open. TEST the system for normal operation.
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H6 CHECK CIRCUIT 1566 (RD/YE) FOR B+
- Disconnect: HVAC Module C228B.
- Measure the voltage between HVAC module C228B-11, circuit 1566 (RD/YE), harness side and ground.
- Is the voltage B+?
Yes
GO to H7.
No
VERIFY Central Junction Box (CJB) fuse 27 (10A) is OK. If OK, REPAIR circuit 1566 (RD/YE) for an open. TEST the system for normal operation. If not OK, REFER to the Wiring Diagrams to identify the possible causes of the circuit short. Diagrams By Number
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H7 CHECK CIRCUIT 1812 (BN/WH) FOR B+
- Ignition ON.
- Measure the voltage between HVAC module C228B-22, circuit 1812 (BN/WH), harness side and ground.
- Is the voltage B+?
Yes
REFER to Module Communications Network Testing and Inspection to diagnose a network concern.
No
VERIFY CJB fuse 15 (10A) is OK. If OK, REPAIR circuit 1812 (BN/WH) for an open. TEST the system for normal operation. If not OK, REFER to the Wiring Diagrams to identify the possible causes of the circuit short. Diagrams By Number
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H8 CHECK THE HVAC MODULE CONNECTION
- Inspect the module connectors for:
- corrosion.
- pushed-out terminals.
- damaged terminals.
- Connect and correctly seat all the HVAC module connectors.
- Clear the DTCs.
- Operate the system and verify the concern is still present.
- Is the concern still present?
Yes
INSTALL a new HVAC module. REFER to Climate Control Service and Repair. TEST the system for normal operation.
No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.
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